1. Field of the Invention
The present invention relates to an integrated circuit package.
2. Description of Related Art
As shown in FIG. 1, an integrated circuit 1 is typically assembled into a package 2 that is soldered to a printed circuit board 3. The package 2 is attached to the board 3 by a plurality of solder joints 4. The integrated circuit package 2 and printed circuit board 3 are typically utilized in an environment which has a varying ambient temperature. A variation in the integrated circuit package temperature will create a different thermal expansion rate between the integrated circuit package 2 and the printed circuit board 3.
The integrated circuit 1 and package 2 have a composite coefficient of thermal expansion (CTE) that is different than the coefficient of expansion of the circuit board 3. Consequently, the package 2 undergoes a different rate of thermal expansion than the circuit board as indicated in phantom on the drawing. This difference in expansion rate produces a strain in the solder joints. When cycled over time it has been found that the mechanical strain may crack the solder joint(s) and create an electrical open between the package 2 and the board 3. It would be desirable to provide an integrated circuit package that compensates for the different CTEs of the package and a printed circuit board to minimize the strain on the solder joints.
Some integrated circuits generate a relatively large amount of heat that must be removed from the package. To minimize the circuit junction temperatures there have been incorporated into the packages various heat conductive members that increase the heat transfer rate from the integrated circuit and the package. The heat conductive member may be a heat pipe that is clamped to the integrated circuit. The clamping force of the heat pipe may create localized stresses that crack and damage the integrated circuit. It would be desirable to have an integrated circuit package that can effectively couple a heat conductive member to an integrated circuit while providing an efficient thermal path between the two devices.